Function and Application of Bone Composition (Carbonate Apatite) Bone Substitute

<p>The inorganic component of bone is not hydroxyapatite but carbonate apatite. Living organisms originated in the sea and formed exoskeletons with calcium carbonate which can be extracted from sea water. On the other hand, the energy of living organisms comes from phosphates such as adenosine triphosphate. Increased mobility, and movement away from the sea, which contains trace amounts of phosphoric acid, to the land (where phosphoric acid does not exist in the air), led vertebrates to store phosphoric acid in their bones. As a result, the skeletal composition of vertebrates became carbonate apatite, which is calcium carbonate with phosphoric acid added.</p><p>Carbonate apatite bone substitute can be prepared by adding phosphate salts to calcium carbonate, inspired by the evolution of the aforementioned organisms. 100％ chemically synthesized carbonate apatite is resorbed by osteoclasts, similar to bones. Due to intercellular information transmission, osteoblasts are activated, demonstrating overwhelming bone conductivity.</p><p>The effectiveness of carbonate apatite has been proven in multi-center trials to be 100％. As a result, carbonate apatite artifical bone substitute has been approved by the PMDA in Japan as the first artifical bone substitute without application restrictions, and is being clinically applied in both Japan and the United States. It holds the top market share in Japan.</p><p>Apatite is essential as a medical device. However, hydroxyapatite is not part of the inorganic composition of bones. For the perspective of treatment effectiveness, there is an urgent need to reconstruct hydroxyapatite-related medical materials with carbonate apatite.</p>